1. Field of the Invention
This invention relates generally to folding, collapsible structures, and more particularly relates to a collapsible, field shelter structure having an elevated canopy.
2. Description of Related Art
Temporary shelters that can be easily transported and rapidly set up at emergency sites can be particularly useful in providing temporary care and housing. Such shelters can also be useful for non-emergency outdoor gatherings, such as for temporary military posts, field trips, and the like. One such quickly erectable, collapsible shelter having a framework of X-shaped linkages, telescoping legs, and a canopy covering the framework is described in my U.S. Pat. No. 4,607,656. The legs of that shelter are capable of telescoping to about two or three times their stowed length, and the framework of X-shaped truss pairs is capable of horizontal extension between the legs to support a canopy. The framework can be constructed of lightweight material, and the telescoping legs can be extended to raise the framework of the shelter. However, the height of the canopy is limited to the extended length of the legs, and the canopy is essentially flat, allowing for collection of precipitation and debris on top of the canopy, which can promote leaks and tears in the canopy. In addition, the size and stability of the shelter is generally limited by the strength of the framework.
It would be desirable to provide an improved collapsible shelter with a support framework for the canopy that rises above the supporting legs, to provide for more headroom within the structure, and to allow for a reduction in the size and weight of the legs and framework required to achieve an adequate height of the canopy. It would also be desirable to provide a canopy structure that is gabled to shed precipitation and debris from the top of the shelter. It would be further desirable to provide a shelter framework that would provide greater strength and stability, to allow support of larger, lighter collapsible shelter structures. The present invention fulfills these needs.
Briefly, and in general terms, the present invention provides for a collapsible shelter with an improved truss framework that raises a gabled shelter canopy to provide increased headroom, strength and stability.
The invention accordingly provides for a collapsible shelter having a canopy with at least three vertically disposed legs supporting the canopy. At least two perimeter truss means are connected to each of the legs. Each of the perimeter truss means preferably includes at least one pair of first and second link members, with the first link member having an outer end connected to the upper end of one leg, and the second link member having an outer end slidably connected to the leg. The first and second link members are pivotally connected together in a scissors configuration so as to be extendable from a first collapsed position extending horizontally between two legs to a second extended position extending above the legs.
In one preferred embodiment, the perimeter truss means includes two essentially identical X-shaped perimeter truss pairs of first and second link members connected together by a central pivot. The two perimeter truss pairs of link members are connected together at their inner ends, and are connected on each side of the collapsible shelter between two adjacent legs. In this embodiment, the collapsible shelter can have three, four, or more sides.
At least two central truss means are also provided, with each of the central truss means including at least one pair of first and second link members connected together in a scissors configuration. Each of the central truss pairs are connected to the inner ends of one perimeter truss means, and the first and second link members are pivotally connected together in a scissors configuration so as to be extendable from a first collapsed position to a second extended position. In a preferred aspect of the invention, tensioning means are also secured between the leg slider member and the central support slider member, to provide additional strength and stability to the framework of the shelter in a raised, extended configuration.
In a preferred four-sided shelter embodiment, two first perimeter truss pairs of link members are connected to each of four legs. For each leg, the outer end of the first link of each truss pair connected to the leg is pivotally connected to the upper end of a leg, and the outer end of the second link is slidably connected to the leg, preferably being pivotally secured to a slider member on the leg. At least two first central truss pairs of link members are also provided, pivotally connected together in a scissors configuration, with each connected to the inner ends of one of the perimeter truss pairs. The outer ends of the central truss pairs are preferably pivotally connected to a junction of the inner ends of the perimeter truss pairs. Each of the central truss pairs preferably includes a first link having an outer end connected to an inner end of at least one of the first links of a perimeter truss pair on a side, an inner end, and a pivot point located at the longitudinal center point of the central truss pair first link. Each of the central truss pairs also preferably includes a second link having an outer end connected to an inner end of at least one of the second links of the perimeter truss pairs on a side, an inner end, and a pivot point located at the longitudinal center point of the central truss pair second link. The second links of the central truss pairs are preferably longer than the first links of the central truss pairs, so that in an expanded configuration of the shelter, the second link extends above the top of the legs. The inner ends of the first or second links of the central truss pairs are further preferably connected to at least one vertically oriented central support member, provided to support the canopy and give the canopy a high pitch, high peaked shape when the shelter framework is in an extended configuration. Tensioning means are also preferably provided between the leg slider member and the central support slider member.
In another embodiment, a three-aided shelter comprises a perimeter framework including two perimeter truss pairs of link members connected to each of the legs with each of the perimeter truss pairs including a first link member pivotally connected to an upper end of a leg, and a second link having an outer end pivotally connected to a leg slider member, slidably connecting the second link to the upper section of the leg. The inner ends of each perimeter truss pair are preferably pivotally connected to the inner ends of another perimeter truss pair at a junction centered between two legs of one side of the shelter framework. Three central truss pairs of link members are also provided, with each of the truss pairs being pivotally connected to the inner ends of at least one of the perimeter truss pairs at the junction. Each of the central truss pairs of link members preferably includes a first link having an outer end connected to the inner end of at least one of the first links of the perimeter truss pairs on a side. Each of the central truss pairs also preferably includes a second link having an outer end connected to the inner end of at least one of the second links of the perimeter truss pairs on a side. The second links of the central truss pairs are preferably longer than the first links of the central truss pairs, so that in an expanded configuration of the shelter, the second link extends above the top of the legs. The inner ends of the first or second links of the central truss pairs are further preferably connected to at least one vertically oriented central support member, provided to support the canopy and give the canopy a high pitch, high peaked shape when the shelter framework is in an extended configuration
These and other aspects and advantages of the invention will become apparent from the following detailed description, and the accompanying drawing, which illustrates by way of example the features of the invention.